Long Range Acoustic Device
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The Long Range Acoustic Device (LRAD) is an acoustic hailing device, sound cannon and sonic weapon developed by LRAD Corporation. Law enforcement organizations and the manufacturer claim that LRAD systems are primarily designed for long-range communications however, the device has an extremely high decibel capacity, and is controversially used as a less-lethal weapon for crowd control.
According to the manufacturer's specifications, the systems weigh from 15 to 320 pounds (6.8 to 145.1 kg) and can emit sound in a 30–60° beam at 2.5 kHz. The manufacturer also produces systems for public address and mass notification use that broadcast 360°.
LRAD systems are used by law enforcement, government and defense agencies, as well as maritime and commercial security companies to broadcast audible notifications and warnings over distance. LRAD systems are also used to deter wildlife from airport runways, wind and solar farms, nuclear power facilities, gas and oil platforms, mining and agricultural operations, and industrial plants.
The parameter "ka", which is the wave number multiplied by the speaker radius, is often used to characterize sound source directivity. For this source, ka=19 at 2.5 kHz, and according to the LRAD data sheet, the beam angle of about 30 degrees total is what is predicted for a regular loudspeaker.
Small spherical "point-source" acoustic devices follow the known inverse square law, which predicts the loss of 6 decibels (dB) per doubling of distance from the source, solely due to geometric spreading. Large speakers (or large arrays), such as these, have an interference pattern in the nearfield which produces peaks 6 dB higher than the output pressure and nulls where the pressure is essentially zero. The larger the speaker, and the higher the frequency, the longer the effective nearfield. The nearfield for this device is approximately 8 metres (26 ft).
LRAD Corporation was formerly named American Technology Corporation.
In addition to its "voice" feature, which acts as a loudspeaker, the LRAD has an "alert" feature, which emits loud chirping sounds that have been reported to cause pain and hearing damage. The LRAD is often considered to be a sonic weapon. The NYPD's LRAD use is being challenged in federal court. Due to potential risks and a lack of studies on the health impact of sonic weapons, the ACLU recommends that their use on protesters be suspended.
Deployments & Uses
LRAD was present, but not used, when the New York City Police department cleared Occupy Wall Street protestors from Zuccotti Park on the morning of 15 November 2011.
LRAD was deployed during a NATO march in Chicago on May 20, 2012, at Michigan Ave. & Cermack.
The Salisbury, MD Police Department acquired an LRAD in October 2013 with proceeds from their speed cameras.
St. Louis County police used LRAD during protests surrounding the police shooting of Michael Brown in Ferguson, Missouri. Reporter Mike Tobin commented while broadcasting from Ferguson, MO on 18 August, "It doesn't have the effect of crippling people. It's just loud, it's annoying, it lets you know something big and official is coming and that's what's happening now. They can also use it as a loudspeaker to tell people to get out of the way."
Myrtle Beach, South Carolina police obtained two LRAD systems through a federal grant in March 2015. Myrtle Beach police captain Marty Brown told the Myrtle Beach city council that "his department is getting the LRADs to enhance their communication capabilities be it with large crowds or for emergency announcements such as evacuation orders."
The NYPD used a Long Range Acoustic Device during the Baltimore solidarity rally in Union Square on April 29, 2015. An NYPD pickup truck equipped with an LRAD parked near protesters and broadcast a looped warning message about staying off the streets and not blocking the sidewalks.
The New Jersey State Police used an armored-vehicle-mounted LRAD to communicate with crowds denied entry to a June 7, 2015 concert after they began throwing bottles and tried to rush the gates outside MetLife Stadium.
The Greensboro, NC Police Department (GPD) purchased an LRAD 300X and demonstrated it for reporters in November 2015. Captain Jonathan Franks with GPD says it can be used for alerts for everything from riots to missing children to weather disasters. "I am sure, positive, 100% that in certain instances it will be able to not only save one life but numerous lives," said Franks.
Police in San Diego, CA used an LRAD on May 27, 2016 to order anti-Trump protesters to disperse.
Police from several agencies, including North Dakota state troopers, the National Guard, and other law enforcement agencies from surrounding counties and states deployed two LRADs to clear a protest camp and blockades along Highway 1806. "Long Range Acoustic Devices, which emit an ear-splitting whine, were used intermittently throughout the day" one reporter wrote. An LRAD was present again on 11/20/2016 at the bridge just north of the protesters camp on highway 1806.
The Columbus, OH Police Department (CPD) demonstrated a Long Range Acoustic Device to the local media on November 21, 2016. CPD expects to use the device for crowd control, barricaded suspect operations, and to communicate to residents during emergencies and natural disasters.
On February 17, 2017, the Princess Anne Police Department deployed its LRAD system at the request of the Maryland State Police to disperse an unruly concert crowd on the campus of the University of Maryland Eastern Shore. Chief Tim Bozman of the Princess Anne Police Department said, "Its a very good piece of equipment for incidents like this."
The Mendocino County (California) Board of Supervisors approved the purchase of a Long Range Acoustic Device for the Mendocino County Sheriff's Office on April 18, 2017. "Sheriff Tom Allman said the device will aid in searches for missing persons, most often hunters and mushroom pickers, which cost the county tens of thousands of dollars. Allman recalled the 2011 search for Aaron Bassler, who had been accused of murdering two men in Fort Bragg and led law enforcement officers on an intense manhunt in the Noyo Basin, saying the LRAD might have made that search a little easier. He said it could also be used to warn residents in case of a tsunami. Last year, MCSO was able to test an LRAD out of a low-flying plane along the coast, and it proved sufficient. He also said the LRAD could prove a valuable asset in a barricaded-person situation (a person hiding out from officers in a building) to communicate from the outside of the building, which has happened before".
The Phoenix, AZ city council approved the purchase of two LRAD 500X systems in November 2018. The speakers will “provide an ability for us to give clear and concise messages to groups of people whenever we find it necessary to communicate with them,” according to Sgt. Mercedes Fortune.
Rochester NY police used verbal warnings and an LRAD to help disperse disorderly crowds during the August 2019 Puerto Rican Festival.
Police utilized a Long Range Acoustic device to declare an unlawful assembly in downtown Phoenix, AZ on May 28, 2020 during the George Floyd protests. Multiple announcements were made in English and Spanish.
During the same period, the LRAD was used at a protest in front of the Arkansas State Capitol.
A BearCat mounted LRAD was used to emit voice messages and high-pitched sirens in Kenosha, WI on August 24, 2020 in front of the Kenosha County Courthouse to disperse crowds assembled in Civic Center Park as part of the Jacob Blake protests.
Rochester, NY police used a Long Range Acoustic Device to make announcements to protesters that they were unlawfully in the roadway and obstructing traffic on September 12, 2020. The device was also used at the September 16, 2020 protest in front of the Rochester city hall.
In September 2020 it was revealed that federal officials had explored the use of the device and the Active Denial System ("heat ray") to disperse civilians protesting outside the White House in June of that year, but had been advised that the National Guard was not currently in possession of either device.
Protesters at the June 1, 2020 Washington, D.C. George Floyd protests said police gave little or no warning before employing aggressive tactics against them. A 2015 settlement requires federal police to give large crowds several loud dispersal orders before deploying chemical irritants and other dispersion tools. Using an LRAD to issue loud protest dispersal orders would have complied with the 2015 settlement requirement.
The Cuyahoga County Sheriff’s Department purchased Long Range Acoustic Devices to improve the department's ability to issue dispersal orders clearly over long distances. The purchases resulted from the department's after-action report of the May 30, 2020 riot in downtown Cleveland.
After receiving feedback last summer from protesters who said commands from on-scene officers were not clear or loud enough, the Seattle, WA mayor's office recommended purchasing an LRAD.
On March 6, 2021, the Boulder Police Department used a toned warble noise from an LRAD in an effort to disperse a crowd of up to 800 students from the University of Colorado Boulder. The University Hill Incident occurred when code enforcement and members of Boulder Police’s Neighborhood Impact Team were unable to disperse partygoers who were congregating against Boulders public health order. LRAD was used after students and other partygoers began throwing rocks at SWAT vehicles and officers. 
On April 12, 2021, the Brooklyn Center, MN Police Department deployed a vehicle mounted LRAD outside of its headquarters to announce curfew violations and dispersal orders to a large crowd protesting the death of Daunte Wright.
Police in Prague used a vehicle-mounted LRAD on 17 November 2020 to repeatedly alert protesters on Wenceslas Square to follow COVID restrictions and wear masks.”
Bad Homburg's fire brigade and city police used an LRAD 100X system more than 60 times in the first half of 2020 for delivering COVID-19 information.”
Hellenic Police acquired two LRAD systems to be used at the Evros border. These were tested after the March 2020 migrant crisis at the border, triggered by the Turkish government. They are to be used as a deterrent against illegal border entry, as a notification system, as well as to handle aggressive actions against the Hellenic Armed Forces.
Japan's Coast Guard used Long Range Acoustic Devices and other methods to expel a North Korean fishing flotilla from its waters in September 2017.
In February 2009, the Japanese whaling fleet operating in Antarctic waters near Australia installed LRADs on their vessels. The device was used against activists of the Sea Shepherd Conservation Society. The Japanese fleet later escalated the use of LRAD, deploying it against a Sea Shepherd helicopter carrying a camera crew. Sea Shepherd noted that they had an LRAD of their own, but as of early 2010, had not put it into use other than to play a recording of "Ride of the Valkyries" in the manner of attacking U.S. Army helicopters depicted in the 1979 film Apocalypse Now.
LRAD was present, but not used because of current legal regulations during protests in Poland, including Million Marijuana March 2011 and Marsz Niepodległości (National Independence Day March) 2011 and 2012. Lacking a way to utilize the LRADs purchased to their full potential sparked an investigation suspecting corruption behind their acquisition. National Police Headquarters spokesman Mariusz Sokolowski defended the purchase of LRAD. He also stressed that the police decided to make this investment because, "We needed good sound reinforcement equipment. With numerous demonstrations and gatherings, police need a public address system that allows you to reach thousands of people."
Local police in Leganés, Spain are using a vehicle-mounted LRAD to deliver alerts and notifications to residents during the country-wide COVID-19 lockdown. According to Citizen Security, Communication and local government spokesman, Oscar Oliveira, “Because the acoustic device can be heard inside of houses, we can inform older residents with mobility issues that all municipal resources are available through the Citizen Attention Service by calling 010.”
Menlo Park and Atherton, CA police and fire officials attended a 'sound off' between a siren installation and an LRAD 360XT mobile voice mass notification system in April 2018. "The side by side test was very helpful and everyone agreed that the LRAD system completely outperformed the older siren system," said Fire District Emergency Manager Ryan Zollicoffer. "Not only because of the voice capability, but the modular-mobility benefit is something that appeals to first responders because it can be used for a variety of public safety purposes and better moved around if that's needed or desired."
The Menlo Park Fire District demonstrated its Long Range Acoustic Device (LRAD) community notification system on April 18, 2019. The fire district also showed how the ShakeAlert system could eventually be tied together with its LRAD to provide area wide audible alerts for earthquake, flood, fire and other emergencies. “ShakeAlert will notify and protect our Station firefighters, but we also believe coupled with the LRAD public address system, it can help to bridge the ‘notification gap’ as another important public safety tool and option for community early warning messaging for earthquakes as well as for fire and flooding information and evacuation signaling," said Fire Chief Harold Schapelhouman.
The City of Laguna Beach, CA installed LRAD speaker sirens in 2018. The systems alert the downtown and Main Beach areas during an emergency where the public needs to take immediate action.
In June 2019, Mill Valley, CA became the first city in the Bay Area to replace its sirens with LRAD community notification systems. The combined siren loudspeakers receive emergency messages via satellite and have back up batteries if the power fails.
The Mill Valley Fire Department began testing its city's new LRAD installations on June 27, 2019. LRAD systems project both siren and voice recordings to alert and inform community members during large-scale disasters. The Long Range Acoustic Devices replaced siren-only systems in five Mill Valley, CA locations. "We believe that the purchase and installation of LRAD goes a long way to improve the resiliency and redundancy of our communication systems," Mill Valley Fire Chief Tom Welch said. "LRAD systems are highly effective in communicating warnings, instructions, and notifications throughout incident sites and over vast areas during life-threatening events."
The City of Newport plans to spend $200,000 to replace three rusty tsunami warning sirens on the Balboa Peninsula with LRAD siren/public address systems. The LRAD systems are expected to be installed by the end of 2019.
In October 2020, Laguna Beach, CA tested its expanded outdoor warning system of 13 Long Range Acoustic Devices mounted on buildings throughout the city. The solar-powered devices broadcast recorded evacuation messages in case cell service is disabled during a disaster
High Seas (Anti-Piracy)
On November 5, 2005, the luxury cruise ship Seabourn Spirit employed an LRAD to repel pirates who attacked the vessel with rocket-propelled grenades about 115 km off the coast of Somalia. The effectiveness of this device during the attack is not completely clear, but the pirates did not succeed in boarding the vessel and eventually fled.
The Liberian vessel MV Biscaglia was attacked on November 28, 2008. The security detachment aboard Biscaglia was reported to have used an LRAD device in an effort to repel attackers armed with assault rifles and rocket-propelled grenades. Following a one-sided shootout, the ship was seized and the unarmed security contractors abandoned ship leaving the ship and crew to the pirates. The incident caused the usefulness of LRADs to be called into question by Lloyd's List.
S/Y Hideaway used an LRAD in 2016 to deter suspected pirates in the Gulf of Aden.
- Algeria: Used for the first time in April 2019 during the pacific walk against Bouteflika on the Algerian population
- Australia: Victoria Police, the Western Australian Police, the South Australia Police, the Queensland Police Service and the Australian Federal Police have confirmed they have purchased the devices.
- Azerbaijan: Azerbaijan police
- Canada: Multiple police departments
- Czech Republic: Used first time on 18 March 2017 by the Police of the Czech Republic
- Hong Kong: Police Tactical Unit and Police Negotiation Cadre (PNC) of the Hong Kong Police Force
- India: Delhi Police
- Israel: Ministry of Defense
- Norway: Norwegian Navy onboard Fridtjof Nansen-class frigates
- Philippines: Philippine National Police, Philippine Coast Guard
- Poland: Polish Police (Polish Police have it but for legal reasons it's not used)
- Romania: Used first time on 7 June 2015 by Jandarmeria Romana
- Singapore: Used by the Singapore Armed Forces
- South Africa: Used by the South African Police Service
- Spain: Reported use by Catalan Police
- Sweden: Swedish Navy
- Turkey: Used by the Turkish Naval Forces
- United Kingdom: Ministry of Defence
- United States: Multiple police departments and US Army
- Vietnam: Being used on-board DN-2000-class ships of the Vietnam Coast Guard's fleet.
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